Engine stringers?

[gbaaron]

Replacing the stringers in a 20' baja, starting with the engine stringers.
The original design looks like it has a two by six board glassed in for the base and then plywood laminated to the top & sides for thickness. Should I use this design or is there something better. has stock 260hp merc. will have 375-400hp when done.

Thanks.

[PowerTech]

I put clear fur wood stringers in my boat wraped in byaxle it is strong.but you could use divinacil foam wraped in byaxle and that would be strong as heck to.

Suggest to build as Carlwun post but for the hull stringers. For engine stringers cores better to use a softwood coated three times with epoxy before glass with biaxiall, You could have also an absorption of engine vibrations and less risk of fatique cracking. Use softwood because in a remote case of water infiltration this could have less expansion then hardwood.

[gbaaron]

Thanks for the reply. Should I use the original design with the 2 by 6 or use all laminated plywood?

Need to look at the boat type; for a 20 ft 6 by 2 looks a little heavy. Send to me a link to look at the boat. Anyway laminated with epoxy is better than timber.

[gbaaron]

Here are some pics of the engine stringers.
Were they are fastened to the transome 2X6, and wider were the engine mounts are.
The other pic is a cutaway after removed from boat

My advise is that You could use laminated plywood to reach the same thickness and dimensions of the stringer on the engine section. Glass them with biaxiall cloth after a few layer of450 gr/mq mat an polyester resin. But is just my advise, laminated softwood glued with epoxy, three pieces of 3/4 " per 6" or so each, then coated with epoxy will be better. You could then glass all with epoxy resin and biaxiall, but don't use mat or use mat without binder, like the constinuous strand one. You will have real strong engine supports and stringers. You could leave others hull stringers in foam core glassed with isophtalic polyester resin or vynil ester (better). Did You use epoxy resin before? Do You can find it or could be a problem?